simplify webpDecodeRGBA and fix test

bench_test.go

@@ -70,27 +70,6 @@ func BenchmarkDecodeRGBA(b *testing.B) {
 	b.StopTimer()
 }
 
-func BenchmarkDecodeRGBAEx(b *testing.B) {
-	data, err := ioutil.ReadFile("./testdata/1_webp_ll.webp")
-	if err != nil {
-		b.Fatal(err)
-	}
-	cbuf := NewCBuffer(len(data))
-	copy(cbuf.CData(), data)
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		m, pix, err := DecodeRGBAEx(cbuf.CData(), cbuf)
-		if err != nil {
-			b.Fatal(err)
-		}
-		_ = m
-		b.StopTimer()
-		pix.Close()
-		b.StartTimer()
-	}
-	b.StopTimer()
-}
-
 func BenchmarkEncodeAndDecode(b *testing.B) {
 	var buf bytes.Buffer
 

capi.go

@@ -26,17 +26,6 @@ package webp
 #include <stdlib.h>
 #include <string.h>
 
-struct cgoWebpDecodeRGBAReturn {
-	int ok;
-	int width;
-	int height;
-	uint8_t* ptr;
-} cgoWebpDecodeRGBA(const uint8_t* data, size_t data_size) {
-	struct cgoWebpDecodeRGBAReturn t;
-	t.ptr = webpDecodeRGBA(data, data_size, &t.width, &t.height);
-	t.ok = (t.ptr != NULL)? 1: 0;
-	return t;
-}
 
 struct cgoWebpEncodeGrayReturn {
 	int ok;
@@ -237,7 +226,8 @@ func webpDecodeGray(data []byte) (pix []byte, width, height int, err error) {
 	}
 	defer C.free(unsafe.Pointer(cptr))
 
-	pix = append([]byte{}, ((*[1 << 30]byte)(unsafe.Pointer(cptr)))[0:len(pix):len(pix)]...)
+	pix = make([]byte, int(cw*ch*1))
+	copy(pix, ((*[1 << 30]byte)(unsafe.Pointer(cptr)))[0:len(pix):len(pix)])
 	width, height = int(cw), int(ch)
 	return
 }
@@ -256,28 +246,29 @@ func webpDecodeRGB(data []byte) (pix []byte, width, height int, err error) {
 	}
 	defer C.free(unsafe.Pointer(cptr))
 
-	pix = append([]byte{}, ((*[1 << 30]byte)(unsafe.Pointer(cptr)))[0:len(pix):len(pix)]...)
+	pix = make([]byte, int(cw*ch*3))
+	copy(pix, ((*[1 << 30]byte)(unsafe.Pointer(cptr)))[0:len(pix):len(pix)])
 	width, height = int(cw), int(ch)
 	return
 }
 
-func webpDecodeRGBA(data []byte, cbuf CBuffer) (pix CBuffer, width, height int, err error) {
+func webpDecodeRGBA(data []byte) (pix []byte, width, height int, err error) {
 	if len(data) == 0 {
 		err = errors.New("webpDecodeRGBA: bad arguments")
 		return
 	}
-	isCBuf := cbuf.Own(data)
-	cData := cgoSafePtr(data, isCBuf)
-	defer cgoFreePtr(cData, isCBuf)
 
-	rv := C.cgoWebpDecodeRGBA((*C.uint8_t)(cData), C.size_t(len(data)))
-	if rv.ok != 1 {
+	var cw, ch C.int
+	var cptr = C.webpDecodeRGBA((*C.uint8_t)(unsafe.Pointer(&data[0])), C.size_t(len(data)), &cw, &ch)
+	if cptr == nil {
 		err = errors.New("webpDecodeRGBA: failed")
 		return
 	}
+	defer C.free(unsafe.Pointer(cptr))
 
-	width, height = int(rv.width), int(rv.height)
-	pix = newCBufferFrom(unsafe.Pointer(rv.ptr), width*height*4)
+	pix = make([]byte, int(cw*ch*4))
+	copy(pix, ((*[1 << 30]byte)(unsafe.Pointer(cptr)))[0:len(pix):len(pix)])
+	width, height = int(cw), int(ch)
 	return
 }
 

reader.go

@@ -15,27 +15,14 @@ import (
 	"os"
 )
 
-func LoadConfig(name string, cbuf ...CBuffer) (config image.Config, err error) {
+func LoadConfig(name string) (config image.Config, err error) {
 	f, err := os.Open(name)
 	if err != nil {
 		return image.Config{}, err
 	}
 	defer f.Close()
 
-	if len(cbuf) == 0 || cbuf[0] == nil {
-		cbuf = []CBuffer{NewCBuffer(maxWebpHeaderSize)}
-		defer cbuf[0].Close()
-	}
-	if len(cbuf[0].CData()) < maxWebpHeaderSize {
-		if err = cbuf[0].Resize(maxWebpHeaderSize); err != nil {
-			return
-		}
-	}
-
-	header := cbuf[0].CData()
-	if len(header) > maxWebpHeaderSize {
-		header = header[:maxWebpHeaderSize]
-	}
+	header := make([]byte, maxWebpHeaderSize)
 	n, err := f.Read(header)
 	if err != nil && err != io.EOF {
 		return
@@ -52,7 +39,7 @@ func LoadConfig(name string, cbuf ...CBuffer) (config image.Config, err error) {
 	return
 }
 
-func Load(name string, cbuf ...CBuffer) (m image.Image, err error) {
+func Load(name string) (m image.Image, err error) {
 	f, err := os.Open(name)
 	if err != nil {
 		return nil, err
@@ -66,32 +53,15 @@ func Load(name string, cbuf ...CBuffer) (m image.Image, err error) {
 	if fi.Size() > (2 << 30) {
 		return nil, errors.New("webp: Load, file size is too large (> 2GB)!")
 	}
-	if len(cbuf) == 0 || cbuf[0] == nil {
-		cbuf = []CBuffer{NewCBuffer(int(fi.Size()))}
-		defer cbuf[0].Close()
-	}
-
-	if len(cbuf[0].CData()) < int(fi.Size()) {
-		if err = cbuf[0].Resize(int(fi.Size())); err != nil {
-			return
-		}
-	}
-	data := cbuf[0].CData()
-	if n := int(fi.Size()); len(data) > n {
-		data = data[:n]
-	}
 
-	_, err = f.Read(data)
-	if err != nil {
+	data := make([]byte, int(fi.Size()))
+	if _, err = f.Read(data); err != nil {
 		return nil, err
 	}
-	m, pix, err := DecodeRGBAEx(data, cbuf[0])
-	if err != nil {
+	if m, err = DecodeRGBA(data); err != nil {
 		return
 	}
-	pix.Close()
-
-	return m, nil
+	return
 }
 
 // DecodeConfig returns the color model and dimensions of a WEBP image without

reader_example_test.go

@@ -21,21 +21,6 @@ func ExampleLoadConfig() {
 	// Height = 301
 }
 
-func ExampleLoadConfig_cbuf() {
-	cbuf := NewCBuffer(0)
-	defer cbuf.Close()
-
-	cfg, err := LoadConfig("./testdata/1_webp_ll.webp", cbuf)
-	if err != nil {
-		log.Fatal(err)
-	}
-	fmt.Printf("Width = %d\n", cfg.Width)
-	fmt.Printf("Height = %d\n", cfg.Height)
-	// Output:
-	// Width = 400
-	// Height = 301
-}
-
 func ExampleLoad() {
 	m, err := Load("./testdata/1_webp_ll.webp")
 	if err != nil {
@@ -45,16 +30,3 @@ func ExampleLoad() {
 	// Output:
 	// Bounds = (0,0)-(400,301)
 }
-
-func ExampleLoad_cbuf() {
-	cbuf := NewCBuffer(8 << 20) // 8MB
-	defer cbuf.Close()
-
-	m, err := Load("./testdata/1_webp_ll.webp", cbuf)
-	if err != nil {
-		log.Fatal(err)
-	}
-	fmt.Printf("Bounds = %v\n", m.Bounds())
-	// Output:
-	// Bounds = (0,0)-(400,301)
-}

webp.go

@@ -48,29 +48,12 @@ func DecodeRGB(data []byte) (m *RGBImage, err error) {
 }
 
 func DecodeRGBA(data []byte) (m *image.RGBA, err error) {
-	pix, w, h, err := webpDecodeRGBA(data, nilCBuffer)
+	pix, w, h, err := webpDecodeRGBA(data)
 	if err != nil {
 		return
 	}
-	defer pix.Close()
 	m = &image.RGBA{
-		Pix:    append([]byte{}, pix.CData()...),
-		Stride: 4 * w,
-		Rect:   image.Rect(0, 0, w, h),
-	}
-	return
-}
-
-func DecodeRGBAEx(data []byte, cbuf CBuffer) (m *image.RGBA, pix CBuffer, err error) {
-	if cbuf == nil {
-		cbuf = nilCBuffer
-	}
-	pix, w, h, err := webpDecodeRGBA(data, cbuf)
-	if err != nil {
-		return
-	}
-	m = &image.RGBA{
-		Pix:    pix.CData(),
+		Pix:    pix,
 		Stride: 4 * w,
 		Rect:   image.Rect(0, 0, w, h),
 	}